Pipe molding apparatus



Jan. 3, 1939. H. H. FARR PIPE MOLDING 'APPARAIUS 5 Sheets-Sheet 1 Filed Nov. 24,- .1937

;%{IWW v (Iitosm an- 1939- H. FARR i 2,142,096

. Y Y PIPE MOLDING APPARATUS,

Filed Nov. 24, 1937 5 Sheets-Sheet 2 Q I Zfnvmtor HERBERT HJ' 'ARR 47 (ltto'megs I 1939- H. H. FARR I 2,142,096

P I PE MOLDING APPARATUS Filed Nov. 24, 1957 S'Sheets-Sheet 4 1 Gttomegs Jan. 3, 193 H. H. FAFeR PIPE MOLDING APPARATUS Filed Nov. 24, 1937 5 Sheets-Sheet 5 Zhwentor Herbal-i Farr (Ittomegs Patented Jan. 3, 1,939

UNlTED STATES 2,142,096 PIPE MOLDING APPARATUS Herbert H. Farr, Alexander City, Ala., assignor to Ferro-Spun Corporation, a corporation of Alabama Application November 2 16 Claims.

This invention relates to mechanism for the in a sand lined-mold or flask.

The centrifugal casting in sand of pipe as at present practiced generally calls for the following sequence of steps, to-wit; the empty flask with its spigot end up and body and hub patterns centered has a sand lining rammed therein; the sand is then struck off at the spigot end of the flask, the body pattern is drawn, and the flask lifted to draw it from the hub pattern; the flask still in upright position is set on a pouring table and faced by the application of a carbonaceous coating composition to the walls of the sand mold; the flask is then laid" horizontal on abed and its sand lining is skin dried after which a hub sand core is mounted in place; the flask in its turn is then placed horizontally on a roll bed and spun or rotated rapidly while the molten metal .is poured into its open spigot end; as soon as the molten metal becomes uniformly distributed about the mold and solidifies, the flask is removed from the roll bed, the sand and casting are shaken out,- and the empty flask is returned to resume the cycle. v

The speed and accuracy with which these various steps can be performed and coordinated obviously determines both the labor cost and the output of a' pipe producing unit, and the objects of my present invention are soto design the flask and its related elements that many of these steps can be carried out with greater ease, speed and accuracy.

For instance, I propose to mount permanently in the flask a' spigot strip plate which is apertured for the introduction of the sand into the flask during the ramming operation; I mount for rotation on.such strip plate an apertured sandstriking plate carrying the spigot flange pattern and serving as a stripping plate for the cylindrical body pattern; I replace the sand striking plate with a spigot-plate and mount same in position to close the apertures in the spigot strip plate and also the spigot end of the mold except for a center pouring opening; I provide a removable hub strip plate adapted to overlap the marginal edge of the hub core while presenting only a corner edge to the metal forming the pipe hub so as to avoid chilling same; I provide the flask with annular end flanges recessed to receive their respective strip and pattern plates and their assembling bolts and only the strip plates and hub core plate are centered by these flanges, the other parts, such as the hub and spigot patterns, and the spigot plate being centered from the inner edges of the strip plates wherebi I avoid any close fits for such removable parts in the end flanges; I use only one pair oi bolts or fastening elements to mount each strip plate in its respective ring and I further secure it by a second pair 4, 1937, Serial No. 176,375

(or. za-m) of bolts or fastening elements which rncunt the related spigot or hub core plate .in the rings; I form a centering ring on the inner face of the spigot plate carrying a. bevelled edge that forms a chill for the spigot end of the pipe and is made 5 wide enough to accommodate pipes having different thicknesses of metal so that a given soil pipe whether of standard, medium, and extra heavy out grade can be cast against the same spigot plate; I form the hub core plate with a 10 hollow body. portion projecting into the hub .core and apertured to vent the moisture from the hub core while it isbeing baked and to assist in venting the gases from the poured flask; and

in a novel manner I mount the pouring spout l5 so as to be guided into and out of the flask and to be readily demountable from its guides to facilitate its inspection, cleaning, and repairing.

My invention further comprises the novel detailsof construction and arrangements of parts 20 which, in their preferred embodiment only, are hereinafter described and claimed, reference being had to the accompanying drawings in which:-- 7 r Fig. 1 is a plan view of a sand lined centrifugal pipe molding apparatus in accordance with my invention with the flask shown in position to be poured on aspinning bed.

V Fig. 2 is a side elevation of Fig. 1, 'partly broken away in vertical central cross-section through the spigot end-of the flask and through the pouring spout. I

Fig. 3 is an enlarged detailed cross-sectional view of a portion of the spigot plate showing the relative size of its flared chill face with relation to the thickness of' standard soil pipe, the dotted lines indicating the extra thickness of medium and extra heavy soil pipe.

'Fig. 4 is a sectional 'view on an enlarged scale taken on the section line IV--IV of Fig. 1; 40

Fig. 5 is an exploded view in vertical crosssection, enlarged, of the spigot end of the rammed flask. V

Fig. 6 15-9. half plan view of the spigot end of the flask with the spigot plate in position.

Fig. '7 is a similar view partly broken away showing the spigot plate removed to expose the spigot strip plate.

Fig. 8is a view corresponding to Figs. 6 and '7 showing the spigot pattern plate in position in the pipe flask after the body portion has been drawn.

Fig. 9 is a vertical central cross-sectional view through the rammed flask showing the body. spigot and hub core patterns in place and the flask broken away.

Fig. 10 is a transverse cross-sectional view through hub end of the flask showing the hub strip plate, and the hub core and core plate, assembled in pouring position.

of the strip plate.

the hub strip plate.

Similar references hereinafter refer to similar parts throughout the drawings. I

In the embodiment of my invention illustrated in the drawings I show conventionally a spinning bed frame l5 having roller bearing shafts I6 journalled in suitable bearings One of the shafts carries a driving pulley l3 driven by suit able belting I9 from a pulley 20 fast on a drive shaft 2|. The shafts |5 carry opposedpairs of grooved rollers 22 which receive the riding rings 23 on the cylindrical centrifugal pipe flask 24 which is adapted to have its rings 23 held in running position on the grooved rollers 22 by grooved hold-down rollers 25, each suitably mounted in a frame 26 which has offset pivotal mounting bY-means of which each hold-down roller is adapted to be swung away from running position and permit the insertion and removal of the flask relative to the spinning frame.

It will be understood that the structural details of the spinning frame and its hold-down rollers may be varied, those shown being of conventional design and suitable for illustrative purposes.

The flask is provided near its center with opposed side trunnions 21 and has a shake out strap 23 attached thereto, all as described and claimed in my companion application Serial No. 176,376 for 9, Sand lined centrifugal pipe mold, executed concurrently herewith,

The flask 24 comprises a cylindrical tubular body perforated throughout for the free venting of moisture and gases therthrough, and at each .end it is externally threaded to receive the threaded hubs of duplicate flanges indicated at 29 and 30 which form countersunk seats, the inner wall of which stands flush with the adjacent flask end. The circumferential. marginal wall 3| of each flange is adapted to receive the related strip plate and pattern elements which will be hereinafter described.

Referring to Figures 5 to 7, the flange 29 at the spigot end of the flask is here shown with the spigot strip plate 32 permanently attached to the flange seat, in close marginal engagement against the flange wall 3|, by means of two screws 33 whose heads are countersunk in the outer face This strip plate has an annu lar series of apertures 34 which define an inner centering ring 35 and leave radial webs 36 connecting same to the plate proper. These aper- 'tures stand with their outer curved edges in register with the internal surface of the flask 24 and form openings through which sand can be freely introduced into the flask during the ramming operation.

After the flask has been rammed a spigot plate 3! is mounted in the flange seat 29 against the strip plate 32 by means of two bolts or like fastening elements 38 which pass loosely through registering holes 39 and 40 provided therefor in the strip plate 32 and the flange 29. It will be noted, however, that this spigot plate 31 does not flt closely against the marginal flange wall 3| but is centered by the shoulder 4| on its inside face which seats snugly within the stripping plate centering ring 35. The thickness of this shoulder .corresponds to that of the strip plate and the is to be cast.

'plate 53.

It will be noted, by reference to Figure that this face 42 is substantially wider than the spigot end 43 ofthe pipe casting which is shown of standard thickness,'while the dotted lines indicateother thicknesses of the spigot end of the pipe casting for medium and extra heavy grades.

From this it will be seen that pipes of a given 7 size having all the thicknesses of different grades are adapted to be cast against the same spigot plate chill face 42. The spigot plate serves to close sand apertures 34 shown in the permanently attached spigot strip plate 32.

In Figs. 8 and 9, I illustrate a spigot pattern and sand striking plate that is set loosely in the flange 29 on the strip-plate 32 during the ramming operation. This pattern plate comprises an annular flat body 45 which has an external diameter less than that of the flange face 3| so that it will flt loosely thereinto and can be turned freely therein. There is provided a series of apertures 46 in this plate 45 approximately corre- 41, corresponding to. 35, which is elongated and shaped to form the pattern 43 for the spigot ring. This pattern 48 is cylindrical and is adapted to snugly fit in the centering ring 35 on the strip plate 32 so as' to be centered thereby. Its internal diameter is such that it will receive and center the body pattern 49 which is scylindrical element having its lower reducedend 50 adapted to be received in, and centered by, the open upper end of the hub pattern 5| that is bolted to a ramming table and serves also to center the flask thereon by the engagement of the base of the pattern 5| with the central opening in the strip The shoulder 52 on the pattern fits loosely in the hub flange 30.

I'mount an opposed pair of outwardly bent handles 10 near the marginal edge of the spigot pattern plate 45 by means of which the'sarne,

while loosely seated on the spigot strip plate 32 may be-rotated, after the ramming operation, to

the operator also by means of these handles holds this pattern plate 45 against the strip plate 32 while the body pattern is being drawn, after which this pattern plate 45 is drawn and is replaced by the spigot plate 31 already described.

Referring to Figs. 9, 10 and 121 show an annular hub strip plate 53 mounted in the hub flange 30 with a snug flt against its face 3| by means of two bolts 54 having their heads countersunk in the under or outer face of the plate 53 and passing through the hub flange 30 to receive nuts which will demountably assemble it in said flange holes being countersunk to receive the bolts 54 and the'other two holes being plain.

When the rammed flask is ready to be poured, I assemble in the hub flange 35 a hub core plate 55 whose outer marginal edge flts snugly within the marginal face 3| of the hub flange, and this plate is apertured to receive two bolts 55 which pass through the strip plate 53 and the hub flange 30 and receive nuts which secure this hub core plate in position.

a The hub core plate is cast with an open center surrounded by an upwardly tapered, frusto-conical body portion 51 provided with side. core vent theflask and adapted to assist in venting gases from the latter during the pouring operation. This body portion 51 is provided with one or more circumferential beads 59 which serve to anchor the hub sand core 60 thereon. This sand core is seated in an annular countersunk recess formed in the core plate 55 between the base of the body 51 and an annular shoulder 6| which is disposed so as to be overhung by the inner peripheral edge of the hub strip plate 53. The base of the 'hub sand core is shaped to form a marginal flange 62, overhung by the hub strip plate, and a shoulder, OI abutting and equal in height with the thickness of said strip plate. end of the flask rests against the strip plate 61 and defines with the core 60 the cavity for the formation of the pipe hub. As shown in Fig. 10, the hub strip plate is not disposed to form a chill for the end of the pipe hub as its upper corner alone borders on the mold cavity without forming an appreciable part thereof.

, Referring to Figs. 1 and 2 it will be noted that I provide a stand 55 at the pouring end of the .spinning frame l5 and mount thereon a slotted slide guide 65 for the pouring spoutG-"l, the guide slot being in line-with the vertical central plane through a flask when in pouring position on the spinning frame, and this slot is'adapted to receive a pair of aligned guide pins 68 depending from the bottom of the pouring spout. These pins may be in the form of bolts adapted to receive nuts, if it be desired to suitably connect the spout to the slide guide, but I prefer to leave the guide pins plain so that the pouring spout can be readily lifted on from the frame for more convenient cleaning, inspection, and repairing. The pouring spout isllined with suitable refractory material indicated in 69 and is provided with a nozzle 'll almost circular in shape with a narrow top slot 12. This nozzle is also lined with a refractory 69 and is substantially coaxial with the flask and with the pouring hole at the center of the spigot plate 31 (see Fig. 4) into which it fits substantially con-' centrically with a marginal clearance all around for the venting of gases from the flask during the pouring operation. I thus provide for venting the flask gases'from both ends of the flask, but the vent opening at either end may be made large enough for all practical purposes. Both vent holes are disposed above the molten metal level in the flask before the same is centrifugally distributed over the whole sand mold surface which is easily arranged in a soil pipe molding flask since the volume of molten metal required for the casting is relatively small.

In Fig. 2 the finished casting I3 is shown in the sand mold after the pouring operation has been carried out on the spinning bed. .To pour a pipe, the flask is lowered'onto the rolls 22 on the spinning bed with its riding rings 23 engaged in the groove of said rolls. The pivoted frames 26 are then rocked into the position to lower the holddown rolls 25 into engagement with the top of the riding rings. The pouring spout 61 is adjusted to the position shown in Fig. 2 and the requisite charge of molten metal, which has been weighed so as to introduce only the correct volume, is thereupon poured into thespout 61 and allowed to flow freely through the nozzle ll into the sand The sand lining 64 at the hub mold within the flask. As the pouring operation is completed the drive is started up and the rolls 22 on the powerdriven shaft [6 start the rotation ,of the flask and bring it up to the requisite speed to effect a centrifugal distribution of the molten v metal over the whole surface of the sand lined mold.- The spinning operation continues. until the casting solidifies, the gases meanwhile making their escape through either or both ends of the flask' which are left open for that purpose.

Whendzhe pouring operation is completed, the

hold-down rolls 25 are lifted and the flask is removed in any desired way from the spinning table to be replaced by the next flask to be poured.

The arrangement of the hold-down rolls is illustrative merely as any convenient or practical means may hold the flasks in driving relation with the rolls 22, which is all that is necessary, I

provided such means will conveniently permit of the introduction and removal of the flask'from the spinning table.

The apparatus is designed to utilize a relatively thin sand lining in the flask, such as can be readily dried during the short interval of time required in continuous casting practice,for.

a rammed flask to advance from the lining stav tion to the spinning table. It is to be noted that the permanently attached spigot strip plate 32 serves as the means for centering all of the other elements associated w'iththe spigot end of the flask from their center outwardly, thus avoiding, the necessity of a close fit between these interchangeable elements and the flask flange 29. At the hub end the hub strip plate 53 and pattern plate55 are the only removable elements that are required to fit snugly into pipe flange 30 to be centered therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims. I a

What I claim .is:--

l. A pipe flask for centrifugal sand molds having at itsv spigot end an annular strip plate mounted in position to define the spigot end of the sand mold and apertured to provide for the admission of sand to the flask during the ramming operation,'a striking plate rotatably' and demountably seated above said strip plate in position to strike off excess sand left above the latter after completion of the ramming operation, said striking plate being also apertured so as to register with the apertured strip plate. and means for rotating said striking plate to strike off said excess sand.

2. A pipe flask for. sand molds having at its spigot end a flange, an annular strip plate attached to said flange and disposed across the spigot end of the flask in position to define the spigot end of the sand mold, said plate being apertured to provide for the admission of sand to the flask, an annular striking plate demountably seated on said strip plate and having sand apertures adapted to register withthe apertures in said strip plate and having at its inner periphery a spigot flange pattern forming an annular bearing adapted to be rotatably engaged within the strip plate, and means to rotate said striking plate to strike ofi the rammed .sand

above said strip plate. V

3. A pipe flask according to claim 2, in which the sand striking plate is centered by the engagement of its said pattern with said strip plate and is adapted to act as a strip plate for a body pattern.

4. A flask for sand molds having at its spigot end a flange forming an annular seat, an annular spigot strip, plate mounted in said seat in position to define the spigot end of the sand mold anda-pertured for the admission of sand.

permanently attached thereto and apertured for the admission of sand into the flask, and a spigot plate demountably attached over said strip plate to close the sand apertures and having a central pouring hole surrounded by an annular flange interfltting with said strip plate and bevelled to form the chill for the end of the pipe spigot. 7

6. A flask according to claim '5, in which said bevelled chill face on the spigot plate is made wide enough for use with pipes varying in thickness of metal at their spigot end.

7. A flask according to claim 5, in which the spigot plate is centeredby means of the engagement of its center flange with an inner peripheral edge of the strip plate.

8. A pipe flask having a strip plate bolted to its spigot end and apertured for the passage of sand therethrough, an annular spigot plate detachably mounted on said strip plate in position to close the apertures therein, and a chill mold ring on said spigot plate adapted to seat in the center of the spigot plate with its inner face bevelled and terminating inwardly substantially flush with the inner face of said strip plate.

9. A pipe flask having an annular hub strip plate and a hub core plate detachably connected thereto in superposed relation, the hub core plate having formed thereon a sand core with a shouldered base adapted to fit snugly in and be centered by the center opening of the strip plate and a marginal flange disposed to be engaged and held between said plates.

10. In combination, a pipe flask having annular strip plates mounted at its ends, hub and spigot pattern, plates detachabiy engaging their respective strip plates and formed with pattern elements which interflt in the center openings of their respective strip plates and are centered thereby in the flask, and a body pattern adapted to be received in and centered by said pattern plates, a plurality of attaching elements, part of which attach only the strip plate to the flask and part of which attach the spigot pattern plate to the flask through the strip plate, whereby the pattern plates are demountable independently of the strip plates.

11.. In a pipe flask, a cylindrical flask body externally threaded at its ends, a flange shaped to provide an annular seat secured to each body end with its seat flush with its respective end,

a strip plateattached to each flange seat by elements having their heads countersunk in said strip plates, a hub core plate seated against the hub strip plate, and a spigot pattern plate seated against the spigot strip plateand bearing a spigot flange pattern which passes'with a close centering fit through the center opening in said spigot strip plate, and handles on said spigot pattern plate for rotating it and holding it in place when serving as a strip plate for a pipe body pattern;

12. In acentrifugalsand lined pipe mold, an annular spigot strip plate and a superposed spigot plate having an annular flange flttedthrough the strip plate and provided at its inner end with an inwardly bevelled end chill face for the spigot flange of the pipe casting.

13. In an apparatus for the centrifugal casting of pipe in a sand lined mold, a flask comprising at its spigot end an annular strip plate mounted in position to deflne the spigot end of the sand mold and adapted to strip' the spigot pattern used to form the spigot print, and a removable spigot plate mounted over said strip plate and having an annular shoulder fitted into the inner periphery of said strip plate and adapted to form a bevellel chill. against which the spigot end of the pipe is cast. I

14. A'pipe flask having a hub flange formed with an annular countersunk seat, and an annular strip plate centered in and detachablyconnected to said seat, in combination with a hub pattern plate having a raised marginal shoulder loosely fitted in said seat and a pattern rigid thereon and centered in said seat only by engagement of the hub pattern base with the inner periphery of said annular strip plate.

15. In combination, a sand lined pipe flask adapted to be jolt rammed with its spigot end up and having annular strip plates mounted in centered relation at its ends, the spigot plate being apertured for the admission of sand to the flask, plates detachably engaging their respective strip plates and formed with pattern elements which interflt in the center openings'of their respective strip plates and form the sole means 0 for centering the pattern plates in the flask throughout the ramming operation, a body pattern adapted to be received in and centered by said pattern plates and, when drawn, to be stripped by said spigot pattern, and means to pouring operation.

16. In a pipe flask, a cylindrical flask body having at each end a flange shaped to provide a spigot flange pattern which passes with a close centering fit through the center opening in said spigot strip plate, and handles on said spigot pattern plate for rotating it and holding it in.

place when serving as a strip plate for a pipe body pattern.

HERBERT H. FARR.

'close the spigot strip plate openings during the 

